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Industrial automation is largely based on PLC-based control systems. PLCs are today mostly programmed in the languages of the IEC 61131 standard which are not ready to meet the new challenges of widely distributed automation systems. Currently, an extension of IEC 61131 which includes object oriented programming as well as the new standard IEC 61499 are(More)
This paper addresses the problem of enforcing generalized mutual exclusion constraints on a Petri net plant. Firstly, we replace the classical partition of the event set into controllable and uncontrollable events from supervisory control theory, by associating a control and observation cost to each event. This leads naturally to formulate the supervisory(More)
To investigate pain and other complications following inguinal hernioplasty performed by the Lichtenstein technique with mesh fixation by fibrin glue or sutures. Five hundred and twenty patients were enrolled in this 12-month observational multicenter study and received either sutures or fibrin glue (Tissucol®/Tisseel®) based on the preference of the(More)
—This paper discusses the problem of controlling a timed Petri net whose marking cannot be measured but is estimated using an observer. The control objective is that of enforcing a set of generalized mutual exclusion constraints (GMEC) and all transitions are assumed to be controllable. We show that the use of marking estimates may significantly reduce the(More)
Extended abstract In this work a new model for urban traffic control is proposed. The main aim in urban traffic control is to maximize the throughput of the system by means of real-time actions [1]. One can, for example, maximize network throughput by dynamically adapting the signal timings in response to changing traffic demand and by coordinating the(More)
BACKGROUND We compared the surgical outcomes in patients undergoing bilateral thyroid surgery with or without parathyroid gland autotransplantation (PTAT). METHODS One thousand three hundred nine patients underwent surgery for treatment of various thyroid diseases at three Academic Departments of General Surgery and one Endocrine-Surgical Unit throughout(More)
In this paper a new approach to fault diagnosis of discrete events systems modeled with Petri nets is presented. Fault events are associated to a subset of unobservable transitions of the net. Negative markings, called generalized marking, are used to estimate the explanations of the observed transitions. The generalized markings allow to cope with the(More)
This paper presents the main vision and research activities of the ongoing European project AIRobots (Innovative Aerial Service Robot for Remote Inspection by Contact, www.airobots.eu). The goal of AIRobots is to develop a new generation of aerial service robots capable of supporting human beings in all those activities that require the ability to interact(More)
Recently a study has been presented for suboptimal supervisory control of Petri nets via monitor (control) places, in the presence of uncontrollable transitions. To enforce a generalized mutual exclusion constraint (GMEC) suboptimally on a plant Petri net with uncontrollable transitions, a set of monitor places has been provided to choose from. There are(More)